About National Today We keep track of fun holidays and special moments on the cultural calendar — giving you exciting activities, deals, local events, brand promotions, and other exciting ways to celebrate. DAY definition: 1. a period of 24 hours, especially from twelve o'clock one night to twelve o'clock the next night…. Learn more. The meaning of DAY is the time of light between one night and the next. How to use day in a sentence. Find out what national day and holiday is today, July 30, 2026. See the full list of today's national days, fun holidays, and awareness days to celebrate right now. 🎉 Browse hundreds of national days, holidays and celebrations. Find today's national days, explore what's coming up this week, and never miss a fun holiday again. A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours (86,400 seconds). As a day passes at a given location it experiences morning, afternoon, evening, and night. This daily cycle drives circadian rhythms in many organisms, which are vital to many life processes. A collection of sequential days is organized into calendars as dates. Discover today's unique celebrations, holidays, and observances on National Today. Find out what makes this day special and worth celebrating! Details about today's date with count of days, weeks, and months, Sun and Moon cycles, Zodiac signs and holidays. The official source for National Days. Find a complete list of today& 039;s holidays, unique celebrations, and fun ways to celebrate every day of the year. Day A day is the time it takes the Earth to spin around once. It is daytime on the side of the Earth that is facing the Sun. When it is nighttime, that side of the Earth is facing away from the Sun. It takes 24 hours for the Earth to spin once, so that is one day, including the daytime and nighttime.